Verification of isomerism and direct measurement of half-lives in184Au

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“…The measurement of 184 Au g+m was especially challenging because the half-lives of both states are rather short: T 1/2m ∼ 45 s and T 1/2g ∼ 20 s [37,38] or T 1/2m = 28 s and T 1/2g = 12 s [39]. For each state, the relative positions of the six resonant lines have allowed the extraction of the magnetic hyperfine constants of the two atomic levels, A and A , the electrostatic hyperfine constant of the final state, B , and the isomeric shift.…”

Identification of a strongly coupled band in deformed odd-odd <sup>184</sup>Au

“…尽管如此, 近年来随着大型射线探测器阵列 投入使用, 人们在对 A≈180 缺中子核区形变双奇核 的高自旋态研究中积累了越来越多的实验数据. 在 本文之前, 人们对形变双奇核 184 Au 核的低自旋态能 级结构进行了一系列研究 [2][3][4][5][6][7][8][9] . Ibrahim 等人 [10] 通过重 离子融合蒸发反应和在束谱学实验方法首次观测到 了 184 Au 核的 4 条转动带, 并对 184 Au 核的高自旋态 能 级 结 构 进 行 了 研 究 .…”

Nuclear Moments and Deformation Change inA184ug,mBlanc1, Obert2, Oms3 et al. 1997Phys. Rev. Lett.460190View full textAdd to dashboardCite

“…The isomeric shift, which is the displacement of the centers of gravity of the two hyperfine spectra, determines the mean square charge radius variation d͗r 2 c ͘ 184g,184m . These measurements are particularly challenging since gold beams are no longer available from 0031-9007͞97͞79(12)͞2213(4)$10.00isotope separators and the half-lives of both states are relatively short (T 1͞2,m ϳ 45 s and T 1͞2,g ϳ 20 s [12,24] or T 1͞2,m 28 s and T 1͞2,g 12 s [25]). We developed the COMPLIS experimental setup [26] which consists of laser desorbing implanted atoms followed by a RIS (resonance ionization spectroscopy) study.…”

“…In this context, the doubly odd nucleus 184 Au with its isomeric state at 68 keV excitation energy [11,12] is particularly interesting to investigate since it is located in the middle of this transitional region [13,14]: States corresponding to prolate and oblate or triaxial shapes coexist in 183,185 Au [9,15,16] and 185 Hg, while 183 Pt is prolate in all its low energy states [17][18][19]. Several nuclear spectroscopy studies were performed on 184 Au, and it has been established that (i) a shape coexistence is excluded at low excitation energy [20], and (ii) the spin and parity are 5 1 for the ground state and 2 1 for the isomer with the following proton-neutron ͑p ≠ n͒ configurations: ph 9 2 ≠ n 7 2 ͓514͔ and ph 9 2 ≠ n 1 2 ͓521͔, respectively [21].…”